1. Field of the Invention
This invention relates to an apparatus for steering a light beam onto a desired target, and more specifically relates to an apparatus for steering a laser beam onto a target in a laser imaging system.
2. Description of the Prior Art
Beam steering apparatus typically include one or more mirrors which redirect, or "steer", a beam emitted by a stationary laser such that a terminal portion of the beam strikes a desired target. The precise location of the laser beam and an angle of incidence of the beam on the target is determined by the relative position of the mirrors.
FIGS. 5(a) and 5(b) show a typical prior art beam steering apparatus 500. The apparatus 500 includes a shaft 510, a first bracket 520 and a second bracket 550 adjustably connected to the shaft 510. A first mirror mount 530 is adjustably connected to the first bracket 520 and a second mirror mount 560 is adjustably connected to the second bracket 550. Mirrors (not shown) are attached to mounting points 533 and 561 respectively formed on the first mirror mount 530 and the second mirror mount 560. The relative angles between the reflective surfaces of the mirrors 540, 570 are adjusted by manipulating knobs 521, 522 located on the first bracket 520, knobs 531, 532 located on the bracket 530, and knobs 551, 552 located on the second bracket 550.
Another approach to steering a light beam is to physically change the position and angular orientation of the light source. For example, in the case of a laser light source, the laser could be physically moved relative to a fixed mirror.
A problem with the prior art beam steering apparatus is that adjustment of the beam is complicated and requires a large amount of space around the apparatus in which to maneuver to effect the desired adjustment.